Stable aqueous dispersions of non-ionic blocked polyisocyanates

ABSTRACT

The present invention relates to stable aqueous dispersions of non-ionic blocked polyisocyanate obtained from the reaction of a polyisocyanate, a blocking agent and a non-ionic alkoxylated diol and to the process for their s preparation; the invention also relates to the use of these aqueous dispersions in textile printing pastes and in the oil and/or water-repellent finishing of textiles.

The present invention relates to a process for the preparation of stableaqueous dispersions of non-ionic blocked polyisocyanates and to thedispersions obtained thereby. The aqueous dispersions of the inventionare especially useful in combination with organic perfluorinatedpolymeric compounds in the oil- and/or water-repellent finishing oftextiles, as they provide an excellent fixing of the organicperfluorinated polymers on textiles and high washing stability of thetreatment.

The process of the invention provides aqueous dispersions of non-ionicblocked polyisocyanates that, unlike the analogous ionic compounds,possess a good compatibility with other adjuvants normally used intextile finishing, independently from their ionicity.

Moreover, the aqueous dispersions of the invention are useful ascross-linkers for textile printing pastes.

One of the problem often encountered in the formulation of aqueousdispersions of non-ionic blocked polyisocyanates is their poorstability.

The process according to the invention allows the obtainment of highlystable aqueous dispersions of non-ionic blocked polyisocyanates.

In the present text with the expression “stable dispersions” we meandispersions having average particle diameters lower than 1000 nm andthat do not show sedimentation after seven days at room temperature.

DESCRIPTION OF THE PRIOR ART

The use of aqueous dispersions of blocked polyisocyanates in textile,paint and coating industry is well known.

In the textile industry, and especially in the finishing of textiles,these dispersions are usually co-formulated with other products, mainlywith fluorocarbon emulsions and/or dispersions and applied onto thearticle by thermal treatment.

During the heating step, the blocked polyisocyanate dissociates so thatthe isocyanate groups become available to react with the active hydrogenatoms that are contained in the fibrous material and/or in theperfluorinated polymer.

As reported in WO 9952961, the dispersions of tonically stabilisedblocked polyisocyanates have the disadvantage that they are notnecessarily compatible with other products of opposite ionicity that aregenerally used in the finishing of textiles, and therefore they can notbe applied in combination with them.

To overcome this problem, WO 9952961 describes the use and production ofnon-ionic blocked polyisocyanates that unfortunately have thedisadvantage to be unstable after being dispersed in water and cannot beeasily used in industrial application.

U.S. Pat. No. 5,693,737 describes the simultaneous presence of an ionicgroup (given by a sulfonate diol) and of an alkoxylated monofunctionallong chain alcohol to stabilise the aqueous dispersions of blockedpolyisocyanates; unfortunately the sulfonate diols used in U.S. Pat. No.5,693,737 are not easily available on the market and their synthesis isnot simple.

DETAILED DESCRIPTION

It has now surprisingly been found that the aqueous dispersions ofnon-ionic blocked polyisocyanates obtained from the reaction of apolyisocyanate, a blocking agent and an non-ionic alkoxylated diolhaving general formula I:

R₂ and R₃ are equal or different and are chosen among methyl, ethyl,n-propyl, i-propyl, n-butyl, i-butyl;

n is a number from 0 to 40;

m is a number from 0 to 40;

n+m is a number from 20 to 80, preferably from 20 to 40, are stable andparticularly suited for the use in the textile field.

The preferred non-ionic alkoxylated diols of the invention have thegeneral formula I:

R₂ is methyl, R₃ is ethyl, n is a number from 15 to 30 and m is a numberfrom 0 to 10; examples of said diols are the commercially availableTegomer® D-3403 and Tegomer® D-3123 from Th. Goldschmidt AG (DE). Thestability of the aqueous dispersions of the present invention is themore unexpected as the use of the analogue mono-functional alcohols,instead of the non-ionic alkoxylated diols, leads to the obtainment ofunstable dispersions that are not suited for the industrial use.

The polyisocyanates utilisable according to the present invention arethose commercially available and containing from 2 to 10 isocyanategroups per molecule and may be either of the aromatic, or the aliphatic,or the cycloaliphatic or the mixed type.

Examples of suitable polyisocyanates include:

A) diisocyanates, such as 1,6-hexamethylenediisocyanate,1-isocyanate-3-isocyanate-methyl-3,5,5-trimethyl-cyclohexane (orisophoronediisocyanate), 4,4′-dicyclohexyl-methanediisocyanate,2,4-toluenediisocyanate either alone or in admixture with2,6-toluenediisocyanate, 4,4′-diphenyl-methanediisocyanate,meta-tetramethylxilylenediisocyanate or mixtures thereof;

B) tri- and higher-functionalised polyisocyanates, such as the compoundsobtained by condensation of trimethylol propane or other polyols havingfunctionality higher than three, and the diisocyanates of point A);

C) compounds obtained by trimerisation, biuretisation, urethanisation orallophanation of the polyisocyanates of the points A) and B), containingat least three isocyanate groups per molecule.

For the realisation of the present invention the preferredpolyisocyanates are the isocyanurate obtained from1,6-hexamethylenediisocyanate and the reaction product of trimethylolpropane and toluenediisocyanate (its isomers 2,4 and 2,6 being in aweight ratio of 80:20).

The blocking agents useful for the realisation of the invention are thenormally used blocking agents of the reversible kind, thermallyde-blockable, such as the compounds containing active methylenic groups(such as the derivatives of malonic acid and its esters, acetylacetone,acetoacetic acid and its esters); oximes; ε-caprolactames and lactames;pyrazoles; imidazoles.

The preferred blocking agents are the ones de-blockable at a temperatureof 90°-160° C.

Particularly useful for the realisation of the present invention areoximes and pyrazoles, and more specifically butanone oxime and3,5-dimethylpyrazole.

According to a fundamental aspect of the invention the process for thepreparation of the aqueous dispersions of non-ionic blockedpolyisocyanates comprises the following steps:

a. a polyisocyanate and a non-ionic alkoxylated diol of the generalformula

R₂ and R₃ are equal or different and are chosen among methyl, ethyl,n-propyl, i-propyl, n-butyl, i-butyl;

n is a number from 0 to 40;

m is a number from 0 to 40;

n+m is a number from 20 to 80, preferably from 20 to 40 are reacted at atemperature of 0°-120° C., their equivalent ratio being such that thepercentage of free isocyanate groups in the resulting oligomer is from 3to 10 and the percentage in weight of ethoxyl groups is from 10 to 40%,preferably from 20 to 30%;

b. the thus obtained oligomer is reacted with an amount of blockingagent such that the equivalent ratio of the isocyanate groups of theoligomer and the blocking agent is from 1:0.98 to 1:1.30, preferablyfrom 1:1 to 1:1,20;

c. the thus obtained mixture is dispersed into water under vigorousstirring to obtain a dispersion having a solid content of from 20 to 40%by weight, preferably from 25 to 35% by weight.

Advantageously, step b. of the process according to the invention may bepreceded by dilution of the reaction mixture obtained in a. with from0.10 to 0.50 parts by weight of a water mixable polar solvent, saidsolvent being removed by distillation after completing of step c.; thepreferred water mixable polar solvents are aliphatic ketones, such asmethyl ethyl ketone, acetone, cyclohexanone.

The process of the invention allows the direct preparation of non-ionicblocked polyisocyanates which are stable for at least six months atambient temperature, without the need of emulsifiers, surfactants orexternal, dispersants.

The dispersions obtained according to the process of the invention canadvantageously be used in the preparation of textile finishing aids, andparticularly in the preparation of compositions for the oil- and/orwater-repellent finishing of textiles containing organic perfluorinatedpolymeric compounds.

Said polymeric compounds are those normally used for these applications;among them we cite:

1) homopolymers of acrylic monomers having general formula:C_(n)F_(2n+1)CH₂CH₂OC(O)—C(R)═CH₂wherein:

R is methyl or hydrogen and n is a number from 5 to 12;

2) homopolymers of acrylic monomers having general formula:C_(n)F_(2n+1)SO₂N(R′)CH₂CH₂OC(O)—C(R)═CH₂wherein:

R and R′ are an alkyl group or hydrogen and n is a number from 5 to 12.

3) copolymers of the above cited fluorinated acrylic monomers with:butadiene, isoprene, chloroprene, styrene, α-methylstyrene,p-methylstyrene, vinyl halides (such as vinyl chloride, vinylidenechloride, vinylidene fluoride), vinyl esters (such as vinyl acetate,vinyl propionate, vinyl stearate), vinyl methyl ketones, esters oracrylic or methacrylic acid (such as methyl acrylate, methylmethacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, butylacrylate, 2-ethylhexyl acrylate or methacrylate, decyl acrylate, laurylacrylate or methacrylate, stearyl methacrylate, N,N-dimethylaminoethylmethacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylateor glycidyl methacrylate), acrylamide, methacrylamide, N-methylolacrylamide, acrylonitrile, methacryloriitrile, N-substituted maleicimides, acrylates or methacrylates of ethoxylated alcohols havingmolecular weight smaller than 2000 daltons or mixture thereof.

For the preparation of the compositions useful for the oil- and/orwater-repellent finishing of textiles, the dispersions of the inventionare normally used in an amount of from 0.1 to 10% by weight on the totalweight of the composition.

Advantageously the weight ratio between the solid fraction of thedispersion of the invention and the perfluorinated polymeric organiccompounds of the oil- and/or water-repellent compositions is comprisedbetween 1:1 and 1:15, more preferably between 1:2 and 1:7.

The finishing step can be performed by using the conventionaltechniques, for example by impregnation or spray technique, at atemperature of from 800 to 110° C. followed by heat treatment at130°-200° C. for 0.5 -6 minutes. The compositions for the oil- and/orwater-repellent finishing of texiles containing the aqueous dispersionsof the invention are stable and the textiles treated therewith exhibithigh washing stability of the finishing.

The aqueous dispersions of the invention are moreover particularlyuseful as cross-linkers for textile printing pastes.

The textiles printed with the printing pastes including the aqueousdispersions of the invention as cross-linkers show high colour andwashing fastness.

For the preparation of the printing pastes, the aqueous dispersion ofthe invention are used in an amount of from 0.3 to 5% by weight,preferably of from 1 to 3.5% by weight, on the total weight of thepaste.

The examples that follow are presented to better illustrate theinvention.

In the examples the following compounds are used:

Polyether 1=Tegomer® D-3403, ethoxylated diol according to theinvention, having molecular weight 1220 g/mol and general formula Iwherein R₁ is (III), R₂ is methyl, R₃ is ethyl, m=0; commercialised byTh. Goldschmidt AG (DE);

Polyether 2=Tegomer® D-3123, ethoxylated and propoxylated diol accordingto the invention (EO/PO: 85/15), having molecular weight 1180 g/mol andgeneral formula I wherein R₁ is (III), R₂ is methyl, R₃ is ethyl;commercialised by Th. Goldschmidt AG (DE);

Polyether 3=polyether mono-alcohol obtained by ethoxylation of butanol,having molecular weight 1400 g/mol;

Polyether 4=polyether mono-alcohol obtained by ethoxylation of butanol,having molecular weight 2000 g/mol;

Polyisocyanate 1=Polurene® AD, reaction product of trimethylol propaneand toluenedilsocyanate (mixture of the isomers 2,4 and 2,6 in a ratio80:20 by weight), having a NCO content of 13.0±0.5% by weight, in ethylacetate (with an active content of 75% by weight); commercialised byS.A.P.I.C.I. S.p.A. (Italy);

Polyisocyanate 2=Tolonate® HDT LV2, product of isocyanuration of1,6-diisocyanatohexane, with an NCO content of 23.0±1% by weight (activecontent of 100% by weight); commercialised by Rhodia (France).

EXAMPLE 1

A reaction vessel, equipped with internal thermometer, stirrer andcooler, is filled, under nitrogen atmosphere and at room temperaturewith 200.0 g (609.756 meq) of Polyisocyanate 1 and 43.4 g ofN-methylpyrrolidone, then 67.0 g (109.756 meq) of Polyether 1 are addedunder stirring. The reaction temperature is brought to 60° C. andmaintained at 60°-65° C. for about two hours, until the titrimetricdetermination of the free NCO-groups still present gives a value of 6.8%by weight (value determined in this example as well as in the otherexamples according to the standard method ASTM D2572).

The reaction mixture is diluted with 100.0 g of acetone and subsequently52.2 g (600.000 meq) of butanone oxime are added dropwise over a periodof about 1 hour, the reaction temperature not exceeding 70° C.

After 1 hour of reaction the prepolymer is checked to be NCO-negativeaccording to the I.R. spectrum and, at about 60° C., 564.3 g ofdemineralised water are added at a high stirring speed.

The organic solvents (ethyl acetate and acetone) are distilled off invacuum. A stable finely divided dispersion is obtained, with solidscontent of 30% by weight, pH 5.58, average particle diameters of 41.4 nm(determined by Coulter N4 Plus).

Percentage by weight of ethylene oxide groups related to the solids=25%IR (cm⁻¹): 3278, 2921, 1727, 1671, 1600, 1536, 1224, 1073, 997, 954,893, 819, 766, 635, 471.

EXAMPLE 2

A reaction vessel, equipped with internal thermometer, stirrer andcooler, is filled, under nitrogen atmosphere and at room temperaturewith 200.0 g (609.756 meq) of Polyisocyanate 1 and 43.0 g ofN-methylpyrrolidone, then 64.8 g (109,756 meq) of Polyether 2 are addedunder stirring. The reaction temperature is brought to 60° C. andmaintained at 60°-65° C. for about two hours, until the titrimetricdetermination of the free NCO-groups still present gives a value of 6.8%by weight.

The reaction mixture is then diluted with 100.0 g of acetone andsubsequently 52.2 g (600.000 meq) of butanone oxime are added dropwiseover a period of about 1 hour, the reaction temperature not exceeding70° C.

After 1 hour of reaction the prepolymer is checked to be NCO-negativeaccording to the I.R. spectrum and, at about 60° C., 559.6 g ofdemineralised water are added at a high stirring speed.

The organic solvents (ethyl acetate and acetone) are distilled off invacuum. A stable milky dispersion is obtained, with solids content of30% by weight, pH 4.86, average particle diameters of 59.7 nm (measuredby Coulter N4 Plus).

Percentage by weight of ethylene oxide groups related to the solids=21%

EXAMPLE 3

A reaction vessel, equipped with internal thermometer, stirrer andcooler, is filled, under nitrogen atmosphere and at room temperaturewith 200.0 g (609.756 meq) of Polyisocyanate 1 and 44.2 g ofN-methylpyrrolidone, then 67.0 g (109.756 meq) of Polyether 1 are addedunder stirring.

The reaction temperature is brought to 60° C. and maintained at 60°-65°C. for about two hours, until the titrimetric determination of the freeNCO-groups still present gives a value of 6.8% by weight.

The reaction mixture is then diluted with 100.0 g of acetone andsubsequently 48.0 g (500.000 meq) of 3,5-dimethylpyrazole are added.

After 1 hour of reaction the prepolymer is checked to be NCO-negativeaccording to the I.R. spectrum and 574.0 g of demineralised water areadded at a high stirring speed.

The organic solvents (ethyl acetate and acetone) are distilled off invacuum. A stable milky dispersion is obtained, with solids content of30%, pH 5.84, average particle diameters of 287.4 nm (measured byCoulter N4 Plus). Percentage by weight of ethylene oxide groups relatedto the solids=25% IR (cm⁻¹): 3270, 2921, 1727, 1669, 1601, 1534, 1451,1413, 1376, 1346, 1283, 1225, 1086, 1001, 968, 883, 817, 764, 744, 678,658, 624, 508, 473, 457, 426.

Example 4 (Comparative)

A reaction vessel, equipped with internal thermometer, stirrer andcooler, is filled, under nitrogen atmosphere and at room temperaturewith 200.0 g (609.756 meq) of Polyisocyanate 1 and 57.9 g ofN-methylpyrrolidone, then 153.7 g (109.756 meq) of Polyether 3 are addedunder stirring. The reaction temperature is brought to 60° C. andmaintained at 60°-65° C. During the reaction the viscosity of thesolution increases more and more, leading to gelification; the additionof 100.0 g of acetone reduces the viscosity only temporary, and thereaction is inevitably stopped.

EXAMPLE 5

A reaction vessel, equipped with internal thermometer, stirrer andcooler, is filled, under nitrogen atmosphere and at room temperaturewith 150.0 g (819.672 meq) of Polyisocyanate 2 and 49.7 g ofN-methylpyrrolidone, then 90.0 g (147.541 meq) of Polyether 1 are addedunder stirring.

The reaction temperature is brought to 60° C. and maintained at 60°-65°C. for about two hours, until the titrimetric determination of the freeNCO-groups still present gives a value of 9.8% by weight. Subsequently64.3 g (739.344 meq) of butanone oxime are added dropwise over a periodof about 1 hour, the reaction temperature not exceeding 70° C.

After 1 hour of reaction the prepolymer is checked to be NCO-negativeaccording to the I.R. spectrum and the reaction mixture is dispersed in640.9 g of demineralised water at a high stirring speed.

A dispersion is obtained with solids content of 30%, pH 5.58, averagepartide diameters of 275.9 nm (measured by Coulter N4 Plus).

Percentage by weight of ethylene oxide groups related to the solids=30%

Example 6 (Comparative)

A reaction vessel, equipped with internal thermometer, stirrer andcooler, is filled, under nitrogen atmosphere and at room temperaturewith 75.0 g (409.836 meq) of Polyisocyanate 2 and 42.5 g ofN-methylpyrrolidone, then 147.5 g (73.770 meq) of Polyether 4 are addedunder stirring.

The reaction temperature is brought to 60° C. and maintained at 60°-65°C. for about two hours, until the titrimetric determination of the freeNCO-groups still present gives a value of 5.3% by weight.

Subsequently 32.3 g (336.066 meq) of 3,5-dimethylpyrazole are addedslowly, the reaction temperature not exceeding 70° C.

After 1 hour of reaction the prepolymer is checked to be NCO-negativeaccording to the I.R. spectrum and 552.1 g of demineralised water areadded at a high stirring speed.

A coarse milky dispersion is obtained, with solids content of 30% and pH6.19.

After 24 hours an evident sedimentation occurs and the average particlediameters can not be measured as it exceed s the upper limit of theinstrument (3000 nm).

Percentage by weight of ethylene oxide groups related to the solids=58%.For easy of consultation the most significant parameters of thedispersions obtained in the Example 1-6 are resumed in the followingTable (Table 1). TABLE 1 R_(EQ) BLOCKING % DISPERSION EX. POLYISOCYANATEPOLYETHER NCO/OH AGENT NCO¹⁾ STABILITY 1 Polyisocyanate 1 Polyether 110/1.8 MEKO³⁾ 8.1 YES 2 Polyisocyanate 1 Polyether 2 10/1.8 MEKO³⁾ 8.1YES 3 Polyisocyanate 1 Polyether 1 10/1.8 3,5-DMP⁴⁾ 7.9 YES 4Polyisocyanate 1 Polyether 3 10/1.8 MEKO³⁾ 6.1 NO 5 Polyisocyanate 2Polyether 1 10/1.8 MEKO³⁾ 9.5 YES 6 Polyisocyanate 2 Polyether 4 10/1.83,5-DMP⁴⁾ 5.5 NO²⁾¹⁾Calculated as % of available Isocyanate groups after de-blocking²⁾after about 2 months the dispersion is completely separated³⁾Butanone oxime⁴⁾3,5-dimethylpirazole

Application Examples

Textile Finishing

Examples 7-9 resume the data obtained from the application testsconducted with the compositions for the oil- and water-repellentfinishing of textiles, prepared with the dispersions described in theExamples 1, 2, 3, 5.

The oil- and water-repellent effect was determined using the testmethods described below.

Water-repellency: the textile samples are evaluated according to MTCC-22(Spray-test).

The water-repellency values are given according to the following scale:100 No wetting, nor water drops on the surface 90 No wetting, but smallwater drops on the surface 80 Surface wetted on spray points 70 Surfacepartially wet 50 Surface totally wet 0 Wetting on the entire surface andback

Oil-repellency: the textile samples are evaluated according to MTCC-118.The oil-repellancy values are attributed according to the followingscale, this test method being based on the resistance to wetting of thefinished fabric by eight different liquid hydrocarbons of varyingsurface tension; the assessment scale in this test method covers gradesfrom 1 to 8, grade 8 being the best (greatest repellent effect). Oilrepellency Composition 1 Liquid paraffin (Kaydol) 2 65:35 -Nujol:n-hexadecane 3 n-hexadecane 4 n-tetradecane 5 n-dodecane 6n-decane 7 n-octane 8 n-heptaneTextile Printing

Example 10 reports the results obtained from the application testsconducted on textile samples printed with the printing pastes preparedusing as cross-linkers the aqueous dispersions of the Examples 1, 2, 5.

The colour fastness of the prints was determined according to UNI 5153,tat describes a method to establish the colour fastness of prints onfabrics of every nature when abraded and the consequent discharge ofcolour onto other fabrics.

The colour fastness was also determined according to UNI 7639, thatdescribes a method to establish the colour fastness of a print onfabrics of different nature under the action of an artificial lightsource.

UNI 5153 describes a test where abrasion is produced by means of a dryfabric and another test where abrasion is produced by means of a wetfabric. An elevated value means a great colour fastness of the printaccording to both tests.

The values are from 1 to 5 according to UNI 5153 and from 1 to 8according to UNI 7639. The washing fastness was also determined. Thetextile samples were washed 3 times at 40° C. (household washing),without intermediate drying and visually evaluated.

Example 7

Cotton fabrics are impregnated at Foulard with the following aqueouscompositions for the oil- and water-repellent finishing of fabrics(Table 2, values expressed as g/l), squeezed in the padding mangle to anapproximately 50% liquor pick-up, dried and baked at 150° C. for 1.5minutes. TABLE 2 Comp. Comp. Comp. Comp. Comp. A B C D EUNIDYNE ®TG470⁽¹⁾ 27 27 27 27 27 MADEOL ® NRW3⁽²⁾ 1 1 1 1 1 Acetic acid1 1 1 1 1 (water sol. 10%) Example 1 5 Example 2 5 Example 3 5 Example 55⁽¹⁾fluorocarbon emulsion commercialised by DAIKIN INDUSTRIES LTD (JP)⁽²⁾surfactant commercialised by Cesalpinia Chemicals SpA (Italy)

After 24 hours of conditioning at room temperature the fabrics aretested with the oil- and water-repellency tests.

The fabrics were also tested after repeated washing cycles.

Washes were performed at 40° C. in a domestic washing machine, using adomestic detergent and dried in tumbler at about 80° C. for 60 min aftereach washing cycle.

The test results are listed in the following table (Table 3). TABLE 3No. of washes Test method 0 1 3 5 Composition A AATCC 22 100 90 70/80 0AATCC 118 4 4 2 2 Composition B AATCC 22 100 100 100 100 AATCC 118 4 6 43/4 Composition C AATCC 22 100 100 100 100 AATCC 118 4 6 3/4 4Composition D AATCC 22 100 100 100 100 AATCC 118 4 6 3/4 3/4 CompositionE AATCC 22 100 100 90 70 AATCC 118 3/4 4 3 2

Example 8

Polyamide fabrics are impregnated at Foulard with the following aqueouscompositions for the oil- and water-repellent finishing of fabrics(Table 4, values expressed as g/l), squeezed in the padding mangle to anapproximately 40% liquor pick-up, dried and baked at 150° C. for 1.5min. TABLE 4 Comp. Comp. Comp. Comp. Comp. A B C D E UNIDYNE ® TG470⁽¹⁾27  27  27  27  27  MADEOL ® NRW3⁽²⁾ 1 1 1 1 1 Acetic acid 1 1 1 1 1(water solution 10%) Example 1 5 Example 2 5 Example 3 5 Example 5 5⁽¹⁾fluorocarbon emulsion commercialised by DAIKIN INDUSTRIES LTD (JP)⁽²⁾surfactant commercialised by Cesalpinia Chemicals SpA (Italy)

After 24 hours of conditioning at room temperature the fabrics aretested in the oil and water repellence tests.

The fabrics were also tested after repeated washing cycles. Washes wereperformed at 40° C. in a domestic washing machine, using a domesticdetergent and dried in tumbler at about 80° C. for 60 min. after eachwashing cycle. The test results are listed in the following table (Table5). TABLE 5 No. of washes Test method 0 1 3 5 Composition A AATCC 22 100100 100 100/90  AATCC 118 3 2 1  0 Composition B AATCC 22 100 100 100100 AATCC 118 3/4 2/3 1/2 1/2 Composition C AATCC 22 100 100 100 100AATCC 118 3/4 2/3 1  0 Composition D AATCC 22 100 100 100 100 AATCC 1183 1/2 1 1/2 Composition E AATCC 22 100 100 100 100 AATCC 118 2 1 1  1

Example 9

Polyester fabrics are impregnated at Foulard with the following aqueouscompositions for the oil- and water-repellent finishing of fabrics(Table 6, values expressed as g/l), squeezed in the padding mangle to anapproximately 30% liquor pick-up, dried and baked at 150° C. for 1.5minutes. TABLE 6 Comp. Comp. Comp. Comp. Comp. Composition A B C D EUNIDYNE ®TG470⁽¹⁾ 27 27 27 27 27 MADEOL ® NRW3⁽²⁾ 1 1 1 1 1 Acetic acid1 1 1 1 1 (water sol. 10%) Example 1 5 Example 2 5 Example 3 5 Example 55⁽¹⁾fluorocarbon emulsion commercialised by DAIKIN INDUSTRIES LTD (JP)⁽²⁾surfactant commercialised by Cesalpinia Chemicals SpA (Italy)

After 24 hours of conditioning at room temperature the fabrics aretested in the oil- and water-repellency tests. The fabrics were alsotested after repeated washing cycles. Washes were performed at 40° C. ina domestic washing machine, using a domestic detergent and dried intumbler at about 80° C. for 60 min. after each washing cycle.

The test results are listed in the following table (Table 7). TABLE 7After washes Finish Test method 0 1 3 5 Composition A AATCC 22 80 0 0 0AATCC 118 4 1 0 0 Composition B AATCC 22 100 90 80 70 AATCC 118 3/4 21/2 1 Composition C AATCC 22 100 90/80 80 70/50 AATCC 118 3/4 1 1 0Composition D AATCC 22 100 90/80 70 70/50 AATCC 118 3 1 1 0 CompositionE AATCC 22 90 70 0 0 AATCC 118 1 1 1 0

Example 10

The printing pastes (paste A, B, C and D) were prepared according to thecompositions listed in Table 8.

The thus obtained printing pastes were used for silkscreen printing onfour cotton fabrics.

Printing was performed onto the Zimmer magnetic table with a 55 wires/cmscreen, by means of a 6 mm roller, at a rate of 50 (grades 10÷100), apressure of 3 (grades 1÷6), in a single step.

After drying at 80° C., the prints were subsequently fixed at 160° C.for 3 min.

The colour fastness of the four cotton fabrics printed with the printingpastes A-D are listed in the following Table 9. TABLE 8 Paste PastePaste Paste g A B C D water 782 782 782 782 DEFOMEX SI⁽¹⁾ 3 3 3 3Ammonia 28 Bè 5 5 5 5 Binder Neoprint L 45⁽²⁾ 150 150 150 150 ClearDP-GP⁽³⁾ 20 20 20 20 Blue Neoprint LBS⁽⁴⁾ 40 40 40 40 Lerisene VHF⁽⁵⁾ 15Example 1 25 Example 2 25 Example 5 25⁽¹⁾Defoamer commercialised by Lamberti S.p.A (Italy)⁽²⁾Ethyl-acrylate aqueous dispersion having an active content of 45%commercialised by Lamberti S.p.A. (Italy)⁽³⁾Syntethic polyacrylate thickener partially neutralised with ammonia;commercialised by Lamberti S.p.A. (Italy)⁽⁴⁾Water dispersion of an organic pigment (C.I. Pigment Blue 15:1);commercialised by Lamberti S.p.A. (Italy)⁽⁵⁾Melamine resin with solids content of 50%; commercialised by LambertiS.p.A. (Italy)

TABLE 9 Test method Evaluation Fabric printed UNI 5153 Dry Wet withPaste A 1/2 4 (comparative) UNI 7639 >6* Fabric printed UNI 5153 Dry Wetwith Paste B 3/4 3/4 UNI 7639 >6* Fabric printed UNI 5153 Dry Wet withPaste C 3/4 4 UNI 7639 >6* Fabric printed UNI 5153 Dry Wet with Paste D4 4 UNI 7639 >6**After 141 h of exposition the degradation of the fabric n° 6 of theblue scale begins, while the cotton fabrics printed with the Paste A-Ddo not show any visible degradation.

The cotton fabrics printed with the printing pastes prepared with thedispersions of this invention (Paste B, C and D) exhibit a washingfastness that is equal to that of the fabric printed with Paste A, whichcontains as cross-linker a standard melamine resin; they exhibittherefore a good washing fastness.

1. Aqueous dispersions of non-ionic —N═C═O blocked polyisocyanatesobtained from the reaction of: (i) a polyisocyanate; (ii) a thermallyde-blockable —N═C═O blocking agent; and (iii) a non-ionic alkoxylateddiol having a general formula I:

and R² and R₃ are the same or different and are selected from the groupconsisting of methyl, ethyl, n-propyl, i-propyl, n-butyl, and i-butyl; nis a number from 0-40; m is a number from 0-40; and n+m is a number from20 to
 80. 2. Aqueous dispersions of non-ionic blocked polyisocyanatesaccording to claim 1, wherein n+m is a number from 20 to
 40. 3. Aqueousdispersion of non-ionic —N—C—O blocked polyisocyanates according toclaim 1 or 2, wherein the non-ionic alkoxylated diol (iii) has thegeneral formula I:

and R₂ is methyl, R₃ is ethyl, n is a number from 15 to 30 and m is anumber from 0 to
 10. 4. Aqueous dispersions of non-ionic —N═C═O blockedpolyisocyanates according to claim 1, wherein the polyisocyanate (i) isan isocyanurate obtained from 1,6-hexamethylenediisocyanate and areaction product of trimethylol propane and toluenediisocyanate. 5.Aqueous dispersions of non-ionic —N═C═O blocked polyisocyanatesaccording to claim 1, wherein the blocking agent (ii) is3,5-dimethylpyrazole.
 6. A process for the preparation of aqueousdispersions of non-ionic —N═C═O blocked polyisocyanates comprising thefollowing steps: a. a polyisocyanate (i) and a non-ionic alkoxylateddiol (iii) of the general formula:

and R² and R₃ are the same or different and are selected from the groupconsisting of methyl, ethyl, n-propyl, i-propyl, n-butyl, and i-butyl; nis a number from 0-40; n is a number from 0-40; and n+m is a number from20 to 80, are reacted at a temperature of 30°-120° C., their equivalentratio being such that the percentage of free isocyanate groups in theresulting oligomer is from 3 to 10 and the percentage in weight ofethoxy groups is from 10 to 40%; b. the thus obtained oligomer isreacted with an amount of a blocking agent (ii) such that the equivalentratio of the isocyanate groups of the oligomer and the blockingagent(ii) if from 1:0.98 to 1:1.30; and c. the thus obtained mixture isdispersed into water under vigorous stirring to obtain a dispersionhaving a solid content of from 20 to 40% by weight.
 7. Process for thepreparation of aqueous dispersions of non-ionic —N═C═O blockedpolyisocyanates according to claim 6, wherein the non-ionic alkoxylateddiols (iii) have the general formula I:

and R₂ is methyl, R₃ is ethyl, n is a number from 15 to 30 and m is anumber from 0 to
 10. 8. Process for the preparation of aqueousdispersions of non-ionic —N═C═O blocked polyisocyanates according toclaim 6, of 7, wherein the polyisocyanate (i) is an isocyanurateobtained from 1,6-hexamethylenediisocyanate and a reaction product oftrimethylol propane and toluenediisocyanate.
 9. Process for thepreparation of aqueous dispersions of non-ionic —N═C═O blockedpolyisocyanates according to claim 6, or 7, or 8, wherein the step b. ispreceded by dilution of the reaction mixture obtained in a. with from0.10 to 0.50 parts by weight of a water mixable polar solvent. 10.Process for the preparation of aqueous dispersions of non-ionic —N═C═Oblocked polyisocyanates according to claim 9, wherein the water mixablepolar solvent is chosen among selected from the group consisting ofmethyl ethyl ketone, acetone, and cyclohexanone.
 11. Process for thepreparation of aqueous dispersions of non-ionic —N═C═O blockedpolyisocyanates according to any of the claims from claim 6 to 10,wherein in step a. the equivalent ratio of polyisocyanate (i) andalkoxylated diol (iii) is such that the percentage in weight of theethoxyl groups is from 20 to 30%.
 12. Process for the preparation ofaqueous dispersions of non-ionic —N═C═O blocked polyisocyanatesaccording to any of the claims from claim 6 to 11, wherein the blockingagent (ii) is chosen selected from the group consisting of butanoneoxime and 3,5-dimethylpyrazole.
 13. Process for the preparation ofaqueous dispersions of non-ionic —N═C═O blocked polyisocyanatesaccording to any of the claims from claim 6 to 12, wherein the amount ofblocking agent (ii) is such that the equivalent ratio of the isocyanategroups of the oligomer and the blocking agent (ii) is from 1:1 to 1:1.2.14. Process for the preparation of aqueous dispersions of non-ionic—N═C═O blocked polyisocyanates according to any of the claims from claim6 to 13, wherein in step c. the mixture is dispersed into water undervigorous stirring to obtain a dispersion having a solid content of from25 to 35% by weight.
 15. Procedure for the oil- and/or water-repellentfinishing of textiles, characterized by the fact that, as a finishingagent, an aqueous composition is used, said aqueous compositioncomprising at least an organic perfluorinated polymeric compounds andfrom 0.1 to 10% by weight of the total weight of the composition, of anaqueous dispersion of a non-ionic —N═C═O blocked polyisocyanatesaccording to claim 1, the weight ratio between the solid fraction of theaqueous dispersion and the perfluorinated polymeric organic compoundsbeing from between 1:1 and 1:15.
 16. A textile printing pastescomprising from 0.3 to 5% by weight of an aqueous dispersion of claim 1.17. The textile printing paste of claim 16, wherein the aqueousdispersion of claim 1 is present at a concentration of from 1 to 3.5%.18. Aqueous dispersion according to claim 4, wherein thetoluenediisocyanate is composed of 2,4 and 2,6 isomers being in a weightratio of 80:20.
 19. Process fro the preparation of aqueous dispersionaccording to claim 8, wherein the toluenediisocyanate is composed of 2,4and 2,6 isomers being in a weight ratio of 80:20.